Gasoline is a zeotropic blend of approximately 500 different hydrocarbons. Gasoline differs in BTU energy content, octane rating, vapor pressure, distillation class, content of ethers and alcohol. Over time, the content of gasoline has changed because of various concerns and regulatory requirements. Lead is banned for on road use because of coating the catalytic converter. Aromatic levels have fluctuated. Benzene is now limited to less than 2/3 of one percent of volume. Ethers, most notably MTBE, have been banned by several states. Oxygenated fuels, reformulated gasoline, and ever evolving federal and state requirements have promoted the use of ethanol as an oxygenate, where it is necessary. Excise and sales taxes on gasoline vary by state. This presentation is aimed at automotive instructors to assist them in providing students relevant knowledge and recommended practices concerning gasoline.